Fry up the bacon, reserving a bit of the bacon grease in the pan. Chop or crumble the bacon into a 13×9-inch casserole dish. Add the onions to the bacon-greasy pan and cook over medium heat for a minute or 2, then add the chopped mushrooms to that. Cook until the mushrooms have released most of their liquid (5 minutes-ish). Add the cooked mushrooms and onions to the bacon in the casserole dish.

Back to the stove. Heat water for the noodles and preheat the oven to 375 deg. F.

While the water is coming to a boil, begin the sauce by melting the butter in a saucepan over medium-high heat. Once the butter is melted, whisk in the flour and continue whisking until it is fully dissolved and pale blond, about 3 minutes. Yup. You’re making a roux. Slowly add the warm milk, stirring constantly until it is incorporated, and continue to stir until it’s smooth. If you want to be all fancy that’s a bechamel sauce. Season the bechamel generously with salt and pepper (white pepper, nutmeg, or crushed red pepper would be fine additions too). Now mix in 1-1/5 c. of cheddar and take it off the heat.

Your water should be boiling, so add the pasta and cook it halfway, about 4 minutes. While that’s cooking, pour the sauce into the casserole with the bacon, mushrooms, and onions and stir it all together. Once the pasta is cooked, add it to the casserole and mix it all up. Mix the remaining cheddar with the other shredded cheese and reserve 1/2 c. for later. Sprinkle the cheese mix over the noodles.

Now, gild the lily.

Arrange a single layer of frozen tater tots to cover the whole casserole dish, Put it in the preheated oven and bake for an hour. Pull the casserole out of the oven and sprinkle the 1/2 cup of cheese that you reserved over the top, then put it under the broiler until the cheese has melted (1-2 minutes).